I personally think this is a bad idea.
Unless you plan on making the requirements to upgrade the new oathbreaker/breeze path require MTS rather than STS and remove it's Moonstone requirements.
You've basically made Moonstones only available to elite/cash players. Which means they control the market prices on them. They are our most rare resource and as people realize this, their prices have become inflated. They have tripled in price since their release.
You're punishing new players, forcing them to P2W. They will have to buy gold to be able to purchase moonstones/STS to upgrade, whereas that was never an issue with Siren / Pirate paths.
There's no way a 400 AP player can go to SPP and PvP vs 600+ AP people to get their moonstones.
I thought you guys were against making this game P2W, yet you continue to provide gambling "events" (you might want to look up the definition of event). Might want to take a page out of Nexon's books and provide ACTUAL events where you GIVE stuff away instead of forcing people to gamble to get stronger.
The only real event we had was the Valentine's event. Everything after that has been a cash cow.
So, now you're saying that you're going to remove the easier weapon paths for new players.
Don't give us your petty BS excuses and just tell us straight up that you're going to make all end game weapon/accessory paths CASH ONLY, in the form of RNG boxes (à la PWI anniversay packs).

So if I had stayed True Siren, I would have been able to skip Pirate completely with this new patch?
If so, that's bogus. Do the people that have True Pirate get something out of it? All that gold and grind wasted?

If it's a 6man dungeon, I really doubt the reason they were leaving was because you weren't 400 attack.
Had you already killed Thrasher? The first boss. If so, they were leaving because they wanted to do their daily quest and that boss is required to do the quest. Highly likely that was the reason you couldn't get people to stay.

It's way too big.... reduce the size of the icons, make the bars thinner. There's no reason for it to be so big... The UI is too busy, everything is way too big =/ When doing main story line, we don't need to see all the past steps in the UI quest log, I can have a main story line that takes up half my screen, it's a bit over the top. Only allow current steps to be shown and cross off the ones we already did in the Quest log (J Key). I like all the shortcuts at the bottom, great for beginners, but once you know what all the keys do you should be allowed to make them invisible.